Having initially hoped to buy a striker and a holding midfielder this month, manager Arsene Wenger was forced into the transfer market for a left-back following a thigh injury to Kieran Gibbs in Wednesday's 2-2 draw against Liverpool.

Interest in Luke Shaw was ended after he committed his future to Southampton, prompting Wenger to bring forward a deal that he had already been lining up with Malaga for Monreal.

Arsenal have a relationship with Malaga through the purchase of Santi Cazorla last summer and they were again able to take advantage of the Spanish club's financial difficulties and need to pay off loans in agreeing a deal for Monreal.